What craziness was my betta doing?

[lyra]

Confused betta owner here!

When I woke up this morning, I got a little concerned because I couldn't see my betta in his tank. After a moment a flash of something at the bottom caught my eye- he was almost burrowed, head first, under some of the ceramic "rocks" at the bottom of the tank (baby biorb) up against the center filter piece.
It looked like only his tail fins were poking out. I got worried that something had happened and unplugged the filter, and he swam right up to the top of the tank. I've never kept a betta in a tank with anything on the bottom of the tank to get into before, so I've never seen them pay much attention to the bottom. Any ideas what he was doing?

Should I be concerned that he could hurt his fins on the ceramic rock things that came with the biorb if he's poking around down there?

[Adastra]

Probably chasing planaria--little worms that live in the gravel and sometimes climb on the glass, nothing to worry about. Definitely make sure nothing sharp is going to be poking out from the bottom, but other than that I wouldn't worry about it.

[vilmarisv]

My first betta did that. I had some bigger river rocks in his tank and he dug himself under them.
I panicked and got him out but unfortunately the damage was already done because her died after a few days.
Now, I only have gravel in my tanks and some crystals. I used to have a little candle holder that served as a cave but one of my bettas liked getting between it and the wall of the tank so I panicked and got rid of it too.

[lyra]

Glad to hear that other bettas do this too!

I decided that the ceramic "rocks" that came with the biorb were a little rough, so they've been out since yesterday, and I'm going to get some marbles to drop down at the bottom instead.


The biorb's filter is kind of raised up in the center of the tank, and the curved edge slopes around to the bottom, which leaves a little bit of space down there. He's definitely been poking around on the bottom a lot, but since I only have plant bases in that area now I think it's OK. Crazy fish.